What is Death's opinion about war in The Book Thief?

Death considers war a lot of work.

Death never gets a vacation.  During war, he has to work a lot of overtime.  For Death, the start of World War II means a lot of extra work.

It was a cool day in Molching when the war began and my workload increased.

The world talked it over.

Newspaper headlines reveled in it.  

The Führer’s voice roared from German radios. We will not give up. We...

Death considers war a lot of work.

Death never gets a vacation.  During war, he has to work a lot of overtime.  For Death, the start of World War II means a lot of extra work.

It was a cool day in Molching when the war began and my workload increased.

The world talked it over.

Newspaper headlines reveled in it.  

The Führer’s voice roared from German radios. We will not give up. We will not rest. We will be victorious. Our time has come.  (Ch. 8)

Hitler is like Death’s new boss, in a way, since he starts the war and wants to kill as many Jews and enemies as possible.  Death is not on Hitler's side.  He is just cleaning up after him.

Deaths never stop in a war.  Death himself feels haunted by humans.  He is distracted by the “leftover” people who watch their loved ones die.  Since Death never gets any time off, he focuses on things that can distract or entertain him, like the color of the sky and the people left behind.  This is why he takes such an interest in Liesel.  He meets her when her brother Werner dies, and finds her a fascinating leftover human.

Death explains that war is like a demanding boss.

To me, war is like the new boss who expects the impossible. He stands over your shoulder repeating one thing, incessantly: “Get it done, get it done.” So you work harder. You get the job done. The boss, however, does not thank you. He asks for more. (Ch. 41)

Death does not like war.  As the war continues, Death keeps working.  He takes an interest in the people who “cheat” him by just escaping death, but he doesn’t resent them.  Death wants to make it clear to us that he is not the one killing people.  All he does is collect the souls of the people who are dead.  It is just a job, and a tough one.  Wartime makes it never-ending.